It has been 21 years since J.K. Galbraith wrote "The Affluent Society." The book was controversial then and is interesting now for its accuracy in predicting some of the major economic trends of the last generation. Today those trends seem to be ending all at once.

Galbraith is an enigma among professional economists. They envy his fame, admire his style and ignore his ideas even though these ideas are occasionally ahead of their time.

Economists ignore his ideas because they are invariably controversial. As a perpetual critic, Galbraith usually defines his position as opposition to the conventional wisdom of his fellow economists. Most people would rather ignore a man who goes through life sticking elegant pins into other people's balloons.

His elegant writing style is also a barrier to the acceptance of his ideas. Like other professions, economics has its own jargon to make it impenetrable to laymen on the general theory that laymen will be impressed by what they can't understand. Like the proverbial Englishman who could not feel both moral and comfortable at the same time, most economists cannot take an idea seriously unless it is presented in a complex and difficult form even though it was Einstein who said, "All things should be made as simple as possible, but not more so."

Galbraith's controversial ideas were summarized in the disarmingly simple phrase "private opulence and public squalor." He observed that the economy did a splendid job of producing private goods and concluded that more resources should be sifted to the public sector to achieve a more desirable "social balance."

The idea that the economy produced more goods and gadgets than people really needed was not popular in an age that honored production and growth. Most people agreed with Samuel Gompers that they wanted "more and more of more and more." In support of his position, Galbraith pointed out that virtually everyone was so provided with the basic necessities that massive advertising was necessary to stimulate artifical wants. A man without shoes does not require a television commercial to tell him what he needs, but a man with a surplus of goods needs strong persuasion to trade in his two-year-old car for one with more chrome and longer tail fins.

By contrast, there is no such advertising to promote demand for the public services that Galbraith found in need of expansion. His solution was to increase taxes to provide more public services such as education, a proposal calculated to gain support of his fellow educators. For the next two decades, this was one of the major trends in the economy as state and local governments' shares of gross national product rose from 10 to 14 percent.

The United States was the first major nation in which the poor were a distinct minority, but Galbraith wanted to eliminate that minority through government spending. A few years later, Lyndon Johnson, not content with merely a good society, proposed a Great Society with a war on poverty as its centerpiece. This helped make Health, Education and Welfare the major growth department of government.

A discussion of peacetime wage and price controls was well ahead of its time. Galbraith had some kind words to say about the subject, a position repellent to virtually everyone, including Nixon up to the time he used them in 1971. In spite of carefully hedged administration assurances, many business executives and labor leaders today fear that continued inflation will bring mandatory controls in an attempt to moderate prices without the pain of recession.

Galbraith was not merely a dispassionate analyst of social trends. He was an active advocate. He intended his book as a call to liberal arms, and he used his talents to accelerate the move toward a larger role for government. He is no Marxist but he understood Marx's dictum, "Philosophers have only interpreted the world. The point, however, is to change it."

A generation of expanding social spending by government has yielded mixed results at best. We educate more students over a longger period but the sharp decline in College Board test scores suggests we do not do it any better. No city embraced the ethic of ever-expanding social spending more fervently than New York, but few would consider it as a model for the future. Sharp increases in welfare spending have improved the medical and living standards of the poor, but opinion polls place welfare toward the bottom of public satisfaction with government.

Virtually every trend eventually generates forces to resist it, and today those forces seem powerful enough to stop the trends Galbraith advocated. Much of the increase in social spending came from reductons in defense from more than 50 percent of federal spending to 25 percent, but now Defense seems to be one of the few departments with the ability to increase its real spending. The current economy mood in government has centered on HEW, which is precisely where the growth of government has been largest.

The most notable symbol of popular dissatisfaction with ever-increasing government is Proposition 13. At this time last year Gov. Jerry Brown of california condemned Propositon 13 as a fraud on the people, but today he embraces a national version in the form of a constitutional amendment to prohibit deficit spending. Such a radical intellectual conversion astonishes many people, but by now Californians are accustomed to a Zen-inspired governor who can consider several incompatible ideas simultaneously and then advocate them all with equal fervor.

Galbraith thought that the economy already produced enough to satisfy the basic needs of most people, but he underestimated how fast they would expand their other needs. A man's stomach sets limits on the amount of food he can eat, but his mind sets no limits on the other goods and services he wants to consume. Once a car was considered a wonderful luxury, but today even a second car is considered a mundane necessity. The economy produces far more than it did a generation ago but few people feel they have more of what they need now than when Galbraith wrote in 1958. The more people have, the more they seem to need to feel they need.

Galbriath's most notable failure was in the one area most resistant to male analysis: female behavior. He suggested that the increasing surplus of goods and services would induce people to work less to gain more leisure time. Women have done the reverse, and today even financially secure housewives are taking jobs to produce an even greater amount of the goods and services that Galbraith suggests are of marginal value to human happiness.

The perverse effect of our current affluence is the compulsion women feel to do more work to produce even more affluence. The flood of women into the work force is one of the most remarkable and poorly explained trends of our time."